Laminated structure of UWB

Abstract

The utility model discloses a UWB laminated structure, comprising a first core plate, a second core plate, a copper-free core plate, a first prepreg, a second prepreg, a third prepreg, a fourth prepreg, a first copper foil layer and a second copper foil layer, and the laminated structure adopts a symmetrical structure of three core plates, four prepregs and two layers of copper foils. The two layers of copper foils are respectively positioned on the top surface and the bottom surface of the laminated structure, so that the laminated structure is formed by pressing at one time, the processing flow is simplified, the production efficiency is improved, and the manufacturing cost is reduced; meanwhile, the first copper foil layer is used for arranging the UWB antenna, the copper foil is hollowed out by the copper-core-free board close to the bottom of the first copper foil layer, no line exists, it is guaranteed that the bottom of the UWB antenna has an enough clearance area, it is guaranteed that signal transmission is not interfered, and the radiation efficiency of the antenna is improved.

Description

Technical Field

[0001] This utility model relates to the field of UWB technology, specifically to a UWB stacked structure. Background Technology

[0002] With the advent of the 5G era, the demand for high-speed data transmission, low latency, and high-precision positioning in wireless communication has increased dramatically. Traditional wireless technologies (such as Wi-Fi and Bluetooth) have limitations in terms of bandwidth, interference resistance, and positioning accuracy. Ultra-wideband (UWB) technology, due to its large bandwidth (typically ≥500MHz), high temporal resolution, low power consumption, and high security, has become a key complementary technology to 5G and is widely used in smart homes, autonomous driving, industrial IoT, and AR / VR fields. However, the performance of UWB systems is highly dependent on the PCB (printed circuit board) layer stack-up design.

[0003] Current laminated structures typically employ a single core board and multiple layers of copper foil, with the copper foil layers bonded to both ends of the core board using prepreg. Because of the multi-layered copper foil structure, at least two bonding processes are required to complete the laminated structure. Furthermore, the top layer of copper foil in the laminated structure is usually used to fabricate the UWB antenna, while the next-top layer copper foil is used to fabricate other circuitry. This other circuitry can easily interfere with the UWB antenna during signal transmission, affecting its performance. Utility Model Content

[0004] Therefore, it is necessary to provide a UWB stacked structure. This addresses the problems mentioned in the background art, such as the requirement of at least two pressing operations for existing stacked structures and the ease with which these structures can interfere with UWB antennas.

[0005] A UWB (Ultra-Wideband) laminated structure includes a first core board, a second core board, a copper-free core board, a first prepreg, a second prepreg, a third prepreg, a fourth prepreg, a first copper foil layer, and a second copper foil layer. The copper-free core board and the second core board are respectively pressed onto both ends of the first core board via the second prepreg and the third prepreg. The first copper foil layer is pressed onto the copper-free core board via the first prepreg, and the second copper foil layer is pressed onto the second core board via the fourth prepreg. The first core board, the second core board, the copper-free core board, the first prepreg, the second prepreg, the third prepreg, the fourth prepreg, the first copper foil layer, and the second copper foil layer are formed by a single pressing. The laminated structure has through holes, and a blind hole is formed between the second copper foil layer and the second core board.

[0006] In one embodiment, the first copper foil layer is used to lay out the UWB antenna.

[0007] In one embodiment, the top surface of the second core board is a GND layer, which provides a low-impedance return path for the signal to ensure impedance continuity; the bottom surface of the second core board is a signal line and power line layer.

[0008] In one embodiment, the second copper foil layer is used to place components.

[0009] In one embodiment, the thickness of the first core board is 1.1 mm.

[0010] In one embodiment, the thickness of the second core board and the copper-free core board is 0.1 mm.

[0011] In one embodiment, the thickness of the first prepreg is 74 μm, the thickness of the second prepreg is 193 μm, the thickness of the third prepreg is 199 μm, and the thickness of the fourth prepreg is 77 μm.

[0012] In one embodiment, the UWB stack has a thickness of 2.0 mm, with a tolerance of ±0.15 mm.

[0013] The aforementioned UWB stacked structure, through the arrangement of a first core board, a second core board, a copper-free core board, a first prepreg, a second prepreg, a third prepreg, a fourth prepreg, a first copper foil layer, and a second copper foil layer, adopts a symmetrical structure of three core boards, four prepregs, and two copper foil layers. Moreover, the two copper foil layers are located on the top and bottom surfaces of the stacked structure, respectively, allowing the stacked structure to be pressed together in one step, simplifying the processing flow, improving production efficiency, and reducing manufacturing costs. At the same time, the first copper foil layer is used to lay out the UWB antenna. The copper-free core board near the bottom of the first copper foil layer has the copper foil hollowed out, with no wiring, ensuring sufficient clearance at the bottom of the UWB antenna, ensuring that signal transmission is not interfered with, and improving the antenna's radiation efficiency. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the stacked structure of UWB according to an embodiment of the present invention. Detailed Implementation

[0015] To make the above-mentioned objects, features, and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a full understanding of this utility model. However, this utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this utility model. Therefore, this utility model is not limited to the specific embodiments disclosed below.

[0016] It should be noted that when a component is considered to be "connected" to another component, it can be directly connected to the other component or there may be an intermediary component present. Conversely, when a component is said to be "directly" connected to another component, there is no intermediary component.

[0017] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0018] like Figure 1 As shown, a UWB laminated structure includes a first core board 1, a second core board 2, a copper-free core board 3, a first prepreg 4, a second prepreg 5, a third prepreg 6, a fourth prepreg 7, a first copper foil layer 8, and a second copper foil layer 9. The copper-free core board 3 and the second core board 2 are respectively pressed onto the two ends of the first core board 1 through the second prepreg 5 and the third prepreg 6. The first copper foil layer 8 is pressed onto the copper-free core board 3 through the first prepreg 4, and the second copper foil layer 9 is pressed onto the second core board 2 through the fourth prepreg 7. The first core board 1, the second core board 2, the copper-free core board 3, the first prepreg 4, the second prepreg 5, the third prepreg 6, the fourth prepreg 7, the first copper foil layer 8, and the second copper foil layer 9 are formed by a single pressing. The laminated structure has through holes 10, and a blind hole 20 is formed between the second copper foil layer 9 and the second core board 2.

[0019] Blind vias serve two purposes: 1. To allow signal traces on BGA chips to fan out (blind vias can be made smaller and can be directly punched onto the pads of the BGA chip, then filled by electroplating backfilling); 2. UWB antennas cannot have vias in certain areas, and the interconnection between the fifth and sixth layers in the UWB antenna area can only be achieved through blind vias.

[0020] The thickness of the first core board 1 is 1.1 mm. The thickness of the second core board 2 and the copper-free core board 3 is 0.1 mm. The thickness of the first prepreg 4 is 74 μm, and the model number is 1080; the thickness of the second prepreg 5 is 193 μm, and the model number is 7628; the thickness of the third prepreg 6 is 199 μm, and the model number is 7628; the thickness of the fourth prepreg 7 is 77 μm, and the model number is 1080. The thickness of the UWB stack structure is 2.0 mm, with an allowable tolerance of ±0.15 mm.

[0021] The first core board 1, the second core board 2, and the copper-free core board 3 are made of Shengyi S1000H material, with a Tg (glass transition temperature) value ≥150°C, DK (dielectric constant) 4.59, and Df (dielectric loss) 0.017.

[0022] The 1080 prepreg has a DK (dielectric constant) of 4.11 and a Df (dielectric loss) of 0.020, while the 7628 prepreg has a DK (dielectric constant) of 4.61 and a Df (dielectric loss) of 0.016. The choice of substrate can increase the complexity and density of the circuit layout within a limited space, greatly improve the quality of signal transmission and the stability of the system, and ensure the overall performance of the product.

[0023] 1080 uses finer glass fiber yarn (typically with a single filament diameter of about 5μm) and has a lower weave density, resulting in a thinner profile. 1080 has a higher resin content (typically about 50%~60%) and a lower glass fiber content, making it more flexible and suitable for filling gaps between multilayer boards. The thinness of 1080 makes it suitable for high-density interconnect (HDI) boards and high-frequency, high-speed boards (such as 5G / UWB), reducing signal loss.

[0024] In one embodiment, the first copper foil layer 8 is used to lay out the UWB antenna. Laying out the UWB antenna with the first copper foil layer 8 increases the effective radiating area of ​​the antenna, thereby achieving high gain.

[0025] The copper foil in the copper-free core board 3 is removed, so that there are no lines in the copper-free core board 3. This ensures that there is enough clearance at the bottom of the UWB antenna, ensuring that the signal transmission is not interfered with and improving the radiation efficiency of the antenna.

[0026] In one embodiment, the top surface 21 of the second core board 2 is a GND layer, which is used to provide a low-impedance return path for the signal and ensure impedance continuity; the bottom surface 22 of the second core board 2 is a signal line and power line layer.

[0027] In this way, the GND layer, as a complete GND layer, provides a low-impedance return path for signals, ensuring impedance continuity; at the same time, it is used for electromagnetic shielding to reduce radiation interference.

[0028] The signal and power lines are arranged on a separate layer, close to the complete ground plane layer of the GND layer, which reduces signal path loss and improves the time domain accuracy of the UWB pulse.

[0029] In one embodiment, the second copper foil layer 9 is used to place components.

[0030] In this way, single-sided component layout is beneficial for SMT placement, improving SMT placement efficiency and reducing PCBA processing costs.

[0031] In this way, the UWB stacked structure, through the arrangement of a first core board, a second core board, a copper-free core board, a first prepreg, a second prepreg, a third prepreg, a fourth prepreg, a first copper foil layer, and a second copper foil layer, adopts a symmetrical structure of three core boards, four prepregs, and two copper foil layers. Moreover, the two copper foil layers are located on the top and bottom surfaces of the stacked structure, respectively, allowing the stacked structure to be pressed together in one step, simplifying the processing flow, improving production efficiency, and reducing manufacturing costs. At the same time, the first copper foil layer is used to lay out the UWB antenna. The copper-free core board near the bottom of the first copper foil layer has the copper foil hollowed out, with no wiring, ensuring that there is sufficient clearance at the bottom of the UWB antenna, ensuring that signal transmission is not interfered with, and improving the antenna's radiation efficiency.

[0032] The embodiments described above are merely illustrative of several implementations of this utility model, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.

Claims

1. A UWB stacked structure, characterized in that: The system includes a first core board, a second core board, a copper-free core board, a first prepreg, a second prepreg, a third prepreg, a fourth prepreg, a first copper foil layer, and a second copper foil layer. The copper-free core board and the second core board are respectively pressed onto both ends of the first core board via the second prepreg and the third prepreg. The first copper foil layer is pressed onto the copper-free core board via the first prepreg, and the second copper foil layer is pressed onto the second core board via the fourth prepreg. The first core board, the second core board, the copper-free core board, the first prepreg, the second prepreg, the third prepreg, the fourth prepreg, the first copper foil layer, and the second copper foil layer are formed by a single pressing. The stacked structure has through holes, and a blind hole is formed between the second copper foil layer and the second core board.

2. The UWB stacked structure according to claim 1, characterized in that: The first copper foil layer is used to lay out the UWB antenna.

3. The UWB stacked structure according to claim 1, characterized in that: The top surface of the second core board is a GND layer, which is used to provide a low-impedance return path for the signal and ensure impedance continuity; the bottom surface of the second core board is a signal line and power line layer.

4. The UWB stacked structure according to claim 1, characterized in that: The second copper foil layer is used to place components.

5. The UWB stacked structure according to claim 1, characterized in that: The thickness of the first core board is 1.1 mm.

6. The UWB stacked structure according to claim 1, characterized in that: The thickness of the second core board and the copper-free core board is 0.1 mm.

7. The UWB stacked structure according to claim 1, characterized in that: The thickness of the first prepreg is 74 μm, the thickness of the second prepreg is 193 μm, the thickness of the third prepreg is 199 μm, and the thickness of the fourth prepreg is 77 μm.

8. The UWB stacked structure according to claim 1, characterized in that: The thickness of the UWB stack structure is 2.0 mm, with an allowable tolerance of ±0.15 mm.

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